Genome-scale CRISPR knockout screen for Dengue, Japanese Encephalitis, and Human Coronavirus 229E viruses
Ontology highlight
ABSTRACT: Unbiased forward genetic screens to identify host factors for DENV1 and JEV in 293FT cells. Unbiased forward genetic screens to identify host factors for HCoV-229E in Huh7.5.1 cells.
Project description:Huh7.5.1 cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, Huh7.5.1 cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the druggable genome library at MOI 0.3. Cells were then selected with puromycin, expanded, and then pooled together and cryofrozen in aliquots. Cells were thawed constituting over 1000× genome coverage worth of mutagenized library. The cells were infecting with DENV2_429557 and DENV-2_16681_Hap1-adapted at MOI of 0.1. Virus-resistant colonies were harvested. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:HT29-DKO cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, 300 million HT29-DKO cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the Brunello library at MOI 0.3. Cells were then selected with puromycin, expanded to 3 billion cells, and then pooled together and cryofrozen in aliquots. One hundred million cells were thawed constituting over 1000× genome coverage worth of mutagenized library. The cells were infecting with PeV-A1 or PeV-A2 at an MOI of 0.1. Virus-resistant colonies were harvested. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:With the near eradication of poliovirus due to global vaccination campaigns, attention has shifted to other enteroviruses that can cause polio-like paralysis syndrome (now termed acute flaccid myelitis (AFM)). In particular, enterovirus D68 (EV-D68) is believed to be the main driver of epidemic outbreaks of AFM in recent years, yet not much is known about EV-D68 host interactions. EV-D68 is a respiratory virus but, in rare cases, can spread to the central nervous system to cause severe neuropathogenesis. We use genome-scale CRISPR screens to identify genes important for EV-D68 infection. A549 and U87-MG cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, 300 million cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the Brunello library (MOI 0.3). Cells were then selected with puromycin, expanded to 3 billion cells, and then pooled together and cryofrozen in aliquots. One hundred million cells were thawed constituting over 1000× genome coverage worth of mutagenized library,expanded, and seeded for the screens. Each screen had over 500x genome coverage. The cells were infected with EV-D68 IL (BEI USA/2014/18952) (MOI 0.1). Virus-resistant colonies were harvested. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:H1-HeLa cells were stably transduced with lentiCas9-Blast (Addgene, Plasmid #52962) and subsequently selected using blasticidin to generate constitutively expressing Cas9 H1-HeLa cells. A single Cas9-expressing H1-HeLa clone was then transduced with lentivirus without a selection marker to stably express CDHR3 C529Y (H1-HeLa+CDHR3). A single CDHR3-expressing H1-HeLa clone was then chosen based on RT-qPCR of CHDR3 expression and RV-C15 RNA levels for mutagenesis. 300 million of the H1-HeLa cells constitutively expressing CDHR3 and Cas9 were transduced with the lentiGuide-Puro from the GeCKO v2 library at a MOI of 0.3. Cells were selected using puromycin and heterogeneous H1-HeLa knockout cell populations were subsequently pooled together. The CRISPR genetic screens were started 10 days post transduction. >1000-fold coverage of mutagenized cells (libraries A and B) was infected with either RV-C15 (MOI=1 PFU/cell) or EV-D68 Missouri (MOI=1 PFU/cell). RV-C15 infection was repeated for an additional round at 6 days post-infection. As soon as appearance of visibly viable colonies was observed, populations of virus-resistant cells were pooled and harvested. Uninfected starting populations of mutagenized cells were used as the unselected reference. Total genomic DNA from both virus-resistant and uninfected cells was respectively extracted using QIAamp DNA Mini Kit (Qiagen). The inserted guide RNA sequences were retrieved from the genomic DNA by PCR amplification. The PCR products were then purified and subjected to NextSeq platform (Illumina) next-generation sequencing.
Project description:eHAP or U87MG cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, 300 million eHAP or U87MG cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the Brunello library at MOI 0.3. Cells were then selected with puromycin, expanded to 3 billion cells, and then pooled together and cryofrozen in aliquots. One hundred million cells were thawed constituting over 1000× genome coverage worth of mutagenized library. Twenty T175 flasks were used for the U87MG-based screen, while twelve T175 flasks were used for the eHAP-based screen. The cells were allowed to recover for 48 hours before infecting with ReoT3D at an MOI of 0.1. Obvious CPE was observed within 72 hours. eHAP-resistant colonies were harvested two weeks later, while U87MG-resistant colonies were harvested six weeks later. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:To search for host factors regulating SARS-COV-2 infection, we performed a genome-wide loss-of-function CRISPR/Cas9 screen in haploid human ESCs. The regulators were identified by the quantification of enrichment of their mutant clones within a pooled loss-of-function library upon SARS-COV-2 infection.
Project description:We undertook a unbiased genome-wide haploid genetic screen to identify new components in interferon lambda signaling. In addition, we performed a genome-wide screen to identify genes that repress spontaneous activation of interferon stimulated genes in the absence of interferon. Both of these screens were performed using a HAP1 cell line containing GFP reporter under the transcriptional regulation of the Interferon-Stimulated Response Element from IFIT2. We also overexpressed IL28RA (IFNLR1) in this cell line, in order to sensitize the cells to type III interferon
Project description:A knockout cell library in Huh7.5.1 cells was generated by introducing a genome-scale CRISPR library (GeCKOv2, Addgene #1000000049) and subjected to hepatitis A virus infection (HM175/18f) to isolate virus-resistant mutant cells. Genomic DNA was isolated from the original and virus-selected mutant cell populations and abundance of guideRNA encoding sequences were measured by sequencing on an Illumina NextSeq (High Output).